. >> and to honor the innocent lives lost. 29-year-old krystle campbell, graduate student lingzi lu, 8-year-old marvin mitch and m.i.t. police officer sean collier. today the streets of copley square are once again open, and the injured are healing from the blast that changed their lives forever. >> we're lucky to be alive. >> adrienne hasler davis was watching the marathon with her husband, air force captain adam davis, who served in afghanistan. how close were you to the second explosion? >> i was right in front of it, right in front of the business where it was, so i felt the direct impact. >> when the first explosion went off, what did you think? >> there was a silence and i thought -- i clung to adam, my husband, and i thought, you know, there's going to be another explosion, and as soon as i thought that i started -- i started saying oh, no, oh, no, oh, no, because you have no idea where it's going to come, from and then all of a sudden i was blown in the air and -- and landed almost in a pretzel with him. >> the blast was so powerful they say they were thrown about five feet.